A seasoned detective named Hei, and his street-smart and alcoholic former partner turned private investigator named Bong, team up in a gruesome murder case that gradually digs out the skeletons in their closets. Bong loses his joie de vivre but later becomes entangled with the happy-go-lucky Feng, while Hei is spinning a dangerous web unbeknownst to his newly wedded wife Susan. Every step of their journey takes them closer and closer to one another, until a shocking denouement in which no stone is left unturned and no one can escape unscathed.